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The Umstead Coalition 
Celebrating Umstead State Park since 1934!

Feasibility Analysis

12/03/2019 8:20 PM | Anonymous

Written by Liz Adams, Research Associate at the UNC Institute for the Environment

The existing Wake Stone Quarry at Harrison Avenue in the Town of Cary mines materials are classified as metavolcanic felsic rocks. The existing hole is 400 feet down, 30 feet below sea level and consists of 140 acres of cleared land that borders I-40 and Umstead State Park.

Felsic rocks contain silica in their name (sic), as they contain greater than 65% silica. The higher the amount of silica, the riskier it is for people to inhale the dust that is generated from mining operations. Exposure to dust that contains silica without adequate protection causes silicosis, which is an incurable lung disease. If you see dust clouds from mining operations, or even if you don’t see them, you may be exposed to harmful levels of silica.

The Environmental Protection Agency provides excellent tools to help communities understand their exposure to harmful air pollution. I examined the online map from the 2014 National Emissions Inventory for our area and couldn’t see any reported emissions of PM2.5 or PM10 from Wake Stone at their RTP location. Even when reported, air emissions are often estimated, rather than measured directly.

There aren’t enough official Air Quality monitoring stations to measure every hazardous or harmful air pollutant in the air across the country as they are very expensive to install and operate. The closest monitor to Umstead State Park is located over 3 miles away at the Triple Oak Station along I-40 near the airport.

The science on the health and environmental effects of PM2.5 is an emerging area of research and scientists are continuing to discover new harmful effects of fine particulate exposure including harmful impacts to every organ in the body.

I have been bicycling and collecting hyper local air quality data using the Plume Flow Sensor for over 6 months. I was concerned about the dust that I had observed at the entrance to the Wake Stone Quarry. I wondered if PM2.5 and PM10 emissions were reaching Umstead State Park, exposing kids who were attending camps, as well as the runners, bicyclists and hikers who use the trails.

Collecting data on PM2.5 concentrations surrounding the existing mine has been an adventure. Riding my bike with the Plume Air Flow monitor has provided me with lots of data. I see it as an opportunity to directly observe and experience winter time inversions caused by cold air aloft that traps pollution at the surface, or rain storms that wash the pollution away. Cycling a regular route down Evans to the new Crabtree Creek Greenway, through Umstead State Park and then back again on the Black Creek Greenway a few times a week for a few months, has helped me to identify multiple sources of pollution and the factors that lead to buildup of the concentration of PM2.5 and PM10 in the air.

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We are a nonprofit dedicated to preserving the natural integrity of William B. Umstead State Park and the Richland Creek Corridor.


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